fastapi

Use `Annotated` for parameters and `Depends()` in FastAPI to improve dependency reusability, automatic documentation, and type-safe validation. This modern pattern replaces older dependency declarations, ensuring cleaner endpoint definitions and maintainable code.

The best way to structure FastAPI endpoints is to declare explicit return types or `response_model` for validation, organize routes using routers, and avoid discouraged defaults like Ellipsis to ensure clean API design conventions.

Choose async vs sync FastAPI handlers based on blocking compatibility. Use async for non-blocking I/O operations and sync for standard blocking tasks to ensure optimal API performance and prevent event loop blocking.

Run the FastAPI server using the modern CLI by defining the app entrypoint in pyproject.toml. This ensures consistent startup behavior for development and production servers, aligning with current FastAPI configuration best practices.

To maintain type-safe APIs, avoid deprecated FastAPI patterns like ORJSONResponse and using Ellipsis for parameter defaults. Instead, use Annotated for dependencies and explicit Pydantic models to reduce bugs and inconsistent code.

Yes, this FastAPI approach works with Pydantic models to ensure type-safe API endpoints. By using modern typing and Annotated parameters, it aligns with current Pydantic patterns for robust request parsing and response validation.